Concrete building unit



June 3, 1930. A. SIITZMAN ET AL 1,761,848

CONCRETE BUILDING UNIT Filed Sept. 28, 1928 Z. $11 will? INVENTOR-S BY {W QM.

- ATTORNEY Patented June 3, 1930 I 1,761,848

UNITED STATES PATENT OFFICE ARTHUR SI'IZMAN, OF BROOKLYN, NEW YORK, AND EDWARD S. KLAUS'NER, OF ASBURY PAR-K, NEW JERSEY concnn'rn BUILDING UNIT Application filed September 28, 1928. Serial No. 309,060.

This invention relates to the production of a precast hollow building unit having a cement building units and more particularly rigid, non-metallic lining for the walls of the is idrected to a novel process and article of hollow portion, said unit being light, simple manufacture comprising a building unit comand cheap to produce, and practical and efiiposed chiefly of either sand, gravel and cient to a high degree in use.

cement, or sand, cinders and cement, or Other objects of this invention will in part Cinders and cement, or sand and cement or be obvious and in part hereinafter pointed other similar cementitious material forming out. aprecast hollow structure. The term pre- The invention accordingly consists in the 19 cast as used hereinafter is applied to disfeatures of production, combinations of eleco tinguish the class of building units that are ments and arrangement of parts which will made and sold in completed form from those be exemplified in the constructions hereinstructures cast or molded in the field of buildafter described and of which the scope of ing operation. application will be indicated in the follow- Building units or blocks of precast holing claims. 6" low form as now produced require relatively In the accompanying drawing, in which is expensive apparatus, skilled labor, and can shown various possible illustrative embodionly be made of limited lengths. The appaments of this invention, ratus includes some form of hydraulic or Figs. 1, 2 and 3 are fragmentary perspecother equivalent presses for compressing the tive views showing portions of precast 70 material to be molded about a temporary core building units embodying the invention. or cores which occupy the space the hollow Fig. 4 is a fragmentary perspective view of is to form, suflicient pressure being applied a conduit using a modified construction of to said material to give it enough strength for improved precast units embodying the inpermitting the removal of the core or cores vention. 75 without collapsing the molding structure. Fig. 5 is a side elevational view of another In practice therefore, the molding of such modified form of construction of the imprecast units are limited 00 about twelve proved precast building units, shown partly inches in length and requires relative high broken away to expose the interior.

grade operators to carry out manufacturing Fi 6 i a cross-sectional view taken on so process since the cement mixture must be carelines 6-6 in Fig. 5. fully prepared and handled to avoid waste of Figs 7, 8, 9 d 10 are di g ti cross the finished product. sectional views showing the progressive steps It is one object of this invention to provide taken in one method for producing the iman improved production of precast buildproved precast hollow building units, and ing units of the character described which Figs. 11, 12 and 13 are similar cross-secmay be of any desired length and shall not be tional views showing the progressive steps of restricted by the process of manufacture as another method for producing the improved heretofore. building units. v

40 Another object of the invention is to pro- As seen from Figs. 1 to 3 of the drawing, 10 Vide a 110ml Process of manufacturing predenotes a building unit constructed to emcast building units of the character debody the invention. Said unit is seen to comscribed which shall be simple and easy to prise an elongated body 11 precast of suitcarry out by relatively unskilled labor withable cementitious materials, as for example,

45 out causing waste of the finished products and in the manner hereinafter described. The

which shall dispense with expensive and body 11 may be of any desired length thatis costly apparatus such as presses, elaborate conveniently handled in building floor sflvalls molds and the like. and ceilings and is not limited or restricted in A further object of the invention is to pro si'ze or relative dimension the process of this: a new article efmanufactur'e comprising manufacture as in the ease of the ordinary 3.6-

ill

building units or blocks of this type now found in general use.

Extending lengthwise through said body 11 there is one or more stiff, hollow members 12 formed of non-metallic sheet material seen to comprise a tubular structure preferably made of cardboard, pulp or straw board, plain or corrugated paper, fibre or other cheap material. Said member 12 is embedded in the body and forms a permanent hollow core therein.

here it is desired to use the improved building units for a conduit, the construction may be modified as shown inFig. 1. The conduit units 110 are each precas with a tubular core 112 permanently embedded in a cen'ientitious body 111 like the unit 10 described above. The end surfaces 111 and 111* of said bedythroughwhich the core 112 extends preferably are formed with suitable interlocking means for registering the cores of adjoining units in exact aligni'ncnt. Said means are here shown as comprising e2;- tension portions 113 at the end 111 of the body and a recess 1141 made to receive the e1:- tension portion 113 on the adjoining unit at the opposite end surface 111 of said body. Since it is often desirable to use relatively long lengths of conduits, the body 111 may be provided with one or more reinforcing bars 115 embedded in the body 111 to extend in s aaced parallel relation to the core member 112. To facilitate handling the conduit units 111 in transportation and installation, the ends 11 1" of the bars are left exposed to serve as handles for lifting or moving the units.

The bar ends 115 may be terminated i'lush with the end surfaces 111 and 111 so as not to interfere with the interlocking alignment of adjoining units as is readily understood 1. cm Fig. 41. The core members 112 for conduits are preferably impregnated with a suitable substance in any well understood manner to render them water or moisture proof or to form a practical dielectric.

in Figs. 5 and 6, a modified construction of precast building unit- 219 is provided. Here the permanent hollow core 212 is made of the samem'aterial as the core 12 described above butforms a complete lining for the walls of the space S within the cementitious body 211 of said unit.

Novel processes for producing the improved building units will now be described.

Referring now toFigsQ't' to 10, inclusive, 20 denotes a mold cast of any well understood construction in which the improved building unit is to be precast. A layer 21 of cementitious material preferable in semi-dry state is placed in the bottom of the cast. The top surface of said layer 21 is next impressed with one or more hollows or recesses 22 shaped to correspond to the contour of the a hollow core 12. Hollow, non-metallic cores are then placed in the recesses 22. The mold is finally filled with ceinentitious material, levelled and pressed or tamped for permanent-1y embedding the cores. The cores being light are easy to handle and are made sufficiently rigid to retain the hollow shaped space during; the molding operation.

In Figs. 11 to 13, inclusive, another simplified method for producing the improved building units is shown. Here the mold cast 20 is partially filled with a layer 31 of wet cementitious material. The hollow cores 12 are placed in a desired spaced position on the top surface 31 of said layer and the mold filled with cementitious material for permanently embedding the cores.

In both methods the cementitious material when dry and hardened form the body 11 of the improved precast building unit.

Since the cores are not removed and form a permanent part of the improved units,the latter may be made any length desired. and are not restricted by the process of manufac' .ture to a size determined by the practical limitation to which the cor s can be removed which form a building hollow unit of standard construction and are approximately twelve inches in length.

While in the above methods. the molding is carried out with the cores lying in a substantial horizontal plane, which has been found more convenient for producing relatively long units, it is to be understood that these methods may be modified for casting the units with the cores in an upright or substantially vertical position.

It should be noted that in using permanent cores in the improved constructions no provision need be made for retaining the shape of the hollows during the molding operation since the cores reinforce the bodies, the walls may therefore be made of minimum thickness and the voids or hollows relatively larger than is possible with the standard constructions. Thus the walls of the box may be relatively thin and of insufficient strength of itself to retain the shape of the unit during the molding operation, since the hollow cores prevent the collapse of the walls during the molding and until the cementitious material has hardened. As a result less material and a lighter building unit can be produced than by the standard methods of manufacture.

Thus simple, cheap and economical sized precast reinforced hollow building units are provided which are easy to produce, re-

quire no other apparatus except a mixer, mold and other small hand tools operated by relatively unskilled labor and which can be made the most economically in bull; and dimensions for erection and transportation since their sizes are not limited or restricted in process of manufacture.

It will thus be seen that there is provided an article and process in which the several sufficient strength of itself to retain the shape ob ects of this invention are achieved and of the unit during the molding operation. which 1s well adapted to meet the conditions In testimony whereof we aifix our signaof practical use. tures.

As various possible embodiments might be ARTHUR SITZMAN. made of the above invention, and as various EDW. S. KLAUSNER.

changes might be made in the embodiments above set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.

Having thus described our invention, we claim as new and desire to secure by Letters Patent:

1. A building unit of the character described comprising a precast cementitious elongated body, a stifl tubular non-metallic member permanently embedded lengthwise through said body, and reinforcing means parallelly spaced from said member embedded in said body, the ends of said means being exposed as and for the purpose described and specified.

2. A building unit of the character described comprising a precast cementitious elongated body, a stiff, tubular, non-metallic member permanently embedded lengthwise through said body, means formed at the ends of said unit for interlocking the latter with the ends of other abutting units, and a bar parallelly spaced from said member embedded in said body, said bar having an end exposed to serve as handling means.

3. A building unit of the character described comprising a cementitious body precast with a permanent stiff hollow core of non-metallic material extending therethrough from end to end, the wall of said body being relatively thin and of insuflicient strength of itself to retain the shape of the unit during the molding operation.

4. A building unit of the character described comprising a precast cementitious elongated body, a stiff tubular non-metallic member permanently embedded lengthwise through said body, and reinforcing means parallelly spaced from said member embedded in said body, the ends of said means being exposed, the wall thickness of said body surrounding said member being substantially less than is required to retain the shape of the unit during the molding operation.

5. A building unit of the character described comprising a precast cementitious elongated body, a stiff, tubular non-metallic member permanently embedded lengthwise through said body, means formed at the ends of said unit for interlocking the latter with the ends of other abutting units, and a bar parallelly spaced from said member embedded in said body, said bar having an end exposed to serve as handling means, the said wall body being relatively thin and of in- 

